1. Field of the Invention
The present invention relates to a multi-axial machine tool and a table unit mounting jig which works a work placed on a work table in a plurality of axial directions.
2. Related Art
As a conventional multi-axial machine tool, there is known a machine tool structured such that a recessed portion is integrally formed in the front-side portion of a column, one half section of a turning table is fitted with and turnably supported by the support surface of the recessed portion which is inclined in a descending manner toward a front side of the machine tool at an angle of 45°, and a table is turnably carried on the upper surface of the other half section of the turning table (see e.g. U.S. Pat. No. 5,669,867 to Hoppe).
Also, as a conventional multi-axial machine tool, there is also known a machine tool structured such that a base table is arranged in the interior of a portal bed disposed on a base in such a manner that it can be moved into and from the interior portion of the portal bed, a turning table is arranged on the base table in such a manner that it can be swung around a swing axis inclined forwardly and upwardly at an angle of 45° with respect to the axis of a spindle, and a work table is turnably supported by the turning table (see e.g. U.S. Pat. No. 4,644,635 to Murai).
However, as disclosed in U.S. Pat. No. 5,669,867, in the case of a structure in which a turning table is fitted with and turnably supported by the inclined surface of a recessed portion formed in a column integrally therewith, the mounting precision of the turning table onto the inclined surface depends on the working precision of the machine tool; and, therefore, it is difficult to adjust the mounting precision and it is also difficult to maintain the mounting precision after adjusted. Also, in case where there arises the need to detach the turning table from the inclined surface because a trouble has occurred in the turning table, it is difficult to detach the turning table.
On the other hand, as disclosed in the above-cited patent literature 2, in the case of a structure in which a turning table is carried on a base table arranged on a leg so as to move into and from the leg, cut chips produced in a cutting operation are easy to accumulate in the interior of the machine tool, which requires a large number of man-hours to remove the accumulated cut chips.